How do i mark emails as read, only when double clicking on it?

[Kyla]

I use to be able to do this but now my computer has changed i can't?

I use to be able to click on an email, and read it via the reading pane but
it wouldn't mark it as read until actually double clicked and opened the
email.

Any ideas on how to do this as i have forgotten!

 

[JeremyH1982]

Right click on the email, and go down to mark as read.